This invention relates to an internal combustion engine and more particularly to an improved, compact and low cost oil pump arrangement for such engines.
Generally four-cycle internal combustion engines are lubricated by an oil pump that is generally positioned within the body of the engine and which is generally driven off of the crankshaft at one end thereof. Such constructions have some disadvantages, particularly when considering that it is also a conventional practice to embody the pressure relief system for the oil pump within the oil pump body. By positioning this part of the engine within the engine body, it tends to elongate the engine, particularly when the accommodation for the relief valve is considered.
With the modern space constraints placed upon internal combustion engines, particularly those for automotive applications, such increases in engine length are unacceptable or undesirable.
It is, therefore, a principal object to this invention to provide an improved, compact and simplified oil pump for an internal combustion engine.
It is a further object to this invention to provide an improved oil pump and relief arrangement for an engine that permits the engine to be compactly constructed.
This invention is adapted to be embodied in an internal combustion engine that comprises an engine body, which defines at least one combustion chamber in which a piston reciprocates. A shaft is driven by the reciprocation of the piston. The shaft has an end portion that extends beyond an outer wall of the engine body. A pulley is affixed to the shaft end portion for driving an engine accessory. An oil pump housing is affixed to the outer wall in surrounding relationship to the shaft end portion and containing a pumping element driven by the shaft end portion for pumping a lubricant for the engine.